Julius Forstmann (1871-1939) settled in the United States in 1904, initially working as a director and vice president of Botany Worsted Mills in Passaic, New Jersey. Shortly following, Forstmann founded the Forstmann and Huffmann Company, also in Passaic, named for the company in Germany he joined in 1897. The Forstmann family had been involved in the in the European woolen industry for generations. In 1931, Forstmann and Huffmann became Forstmann Woolen Company, a firm recognized as the "leading manufacturer of fine woolen and worsteds in America." At that time, the Company operated 60,000 spindles and 1,000 broad looms. Forstmann designed his own fabrics, founded the National Quality Maintenance League, and was a sponsor of the "Truth-in-Fabrics" bill passed by Congress in 1940. The bill required manufacturers to list the content of fabric with the garment or other item produced. Forstmann provided educational opportunities for his employees and their families through a vocational institute named for Forstmann, funded largely by a foundation established in memory of his second son, Carl Edward Forstmann. While the Forstmann Woolen Company excelled in the manufacture of fine material, the Julius Forstmann & Company, Inc. was established as its fiscal and selling agent. While separate in purpose, these companies overlapped in that one family member might oversee the operations of both companies. Julius Forstmann served as chairman of the board of the Forstmann Woolen Company until 1938 and as president of the Julius Forstmann & Company, Inc. from 1938 until his death the following year.

When Julius Forstmann died in 1939, Curt Erwin Forstmann (1907-1950) assumed responsibility for the Woolen Company's operations, serving as president until his death in 1950. In 1949, he became chairman of the board of directors. Under his direction, the company manufactured fabric for the U.S. Government during World War II. Julius George Erwin (1909-1962), a younger brother of Curt Erwin, served as a director of the company in 1933, vice president in 1934, and, following Curt Erwin's death, was named president and chairman of the board of the Forstmann Woolen Company and served through 1957. Under his direction, the company acquired the Louis Gallet Knitting Mills in 1956. Other subsidiary companies include Super-Tex, Inc., Skaneateles Teasel Company, Garfield Warehouse and Terminal Company, and the Credit and Investors Advisory Corporation, later the Economic Advisory Corporation. Julius George Forstmann also served as president, treasurer, and director of the Julius Forstmann & Company, Inc. until 1957 when both companies were acquired by J. P. Stevens. At that time, the Company marketed fine woolens and worsteds for women's coats, suits, dresses, hosiery, and sweaters, as well as men's wear. From 1957 until his death in 1962, Julius George Forstmann provided services as a consultant to the Stevens Company while continuing as chair of the Forstmann division until its liquidation in 1960.

While substantive information on the subsidiary companies is not readily available, some information can be gleaned from the ledgers in the collection. The Credit and Investors Advisory Corporation, later the Economic Advisory Corporation (1950-1953), was established in June 1946 and continued until June of 1953 with the purpose of providing investment and business advisory services. Julius Forstmann & Co., Inc. was the sole stockholder of the company. Garfield Warehouse & Terminal Company operated out of New Jersey and was established in 1943; in 1955 the directors considered and accepted a vote to dissolve the company. Louis Gallet Knitting Mills, acquired by the Forstmann Companies in 1956, had been in operation since the late 1940s, initially as East Millsboro Gallet Knitting Mills. The Skaneateles Teasel Co. was incorporated on October 9, 1920 and dissolved October 11, 1927. The company was organized in Newark, NJ for the purpose of "trading and grading teasels used in cloth manufacture." Super-Tex., Inc. was organized in New York City in 1920 and also dissolved in 1927. Forstmann and Huffmann acquired the assets of the company.